The autonomic nervous system has been stimulated to modulate various physiologic functions, such as cardiac functions and hemodynamic performance. The myocardium is innervated with sympathetic and parasympathetic nerves. Activities in these nerves, including artificially applied electrical stimuli, modulate the heart rate and contractility (strength of the myocardial contractions). Neural stimulation that elicits a parasympathetic response (e.g. stimulating nerve traffic at a parasympathetic neural target such as a cardiac branch of the vagus nerve and/or inhibiting nerve traffic at a sympathetic neural target) is known to decrease the heart rate and the contractility, lengthen the systolic phase of a cardiac cycle, and shorten the diastolic phase of the cardiac cycle. Neural stimulation that elicits a sympathetic response (e.g. stimulating nerve traffic at a sympathetic neural target and/or inhibiting nerve traffic at a parasympathetic neural target) is known to have essentially the opposite effects. The ability of the electrical stimulation of the autonomic nerves in modulating the heart rate and contractility may be used to treat abnormal cardiac conditions, such as to improve hemodynamic performance for heart failure patients and to control myocardial remodeling and prevent arrhythmias following myocardial infarction. The autonomic nervous system regulates functions of many organs of the body. Vagus nerve stimulation, for example, affects respiration as the vagus nerve includes many lung, bronchial and tracheal afferents that feed into the respiratory centers of the brainstem.